Policy Feature Card is primarily responsible for forwarding the packets. The MSFC is responsible for building the routing table, peering with neigbour routers.

You need an MSFC to route traffic at layer 3.

L3 forwarding is routing. It is often called layer 3 switching on Catalysts which basically means there are dedicated ASIC's(Application Specific Intergrated Chip) for the L3 forwarding as opposed to routers which use software.

Yes i agree, sometimes Cisco can make it quite hard to understand things but the 6500 is a complicated piece of kit :)

Attached is a link to an architecture paper on the 6500 which explains all the functions of the PFC/MSFC cards.

Jon, I have known for 10 years or so that an MSFC is the L3 switching (routing) engine. I must have configured 100 of them. But its the language Cisco used that was confusing me....glad you did that sanity check for me. LOL